BOB BARNARD:

Six suicidal terrorists were among those killed in a car bombing at the U.S. Embassy in Yemen overnight.

SEAN MCCORMACK, STATE DEPARTMENT SPOKESMAN:

This attack bears the hallmarks of an Al Qaeda attack. The kinds of attacks we've seen in the past.

BARNARD:

Al Qaeda wants the U.S. out of Muslim lands and for Israel to be destroyed, but are the terrorists now trying to influence our presidential election by reminding us there's more to fear than the faltering U.S. economy?

STEVE EMERSON:

If they had killed Americans, it would have made many more headlines, which is what they tried to do of course.

BARNARD:

Terrorist investigator Steve Emerson has studied Al Qaeda for years and says bin Laden's followers have reasons to want either McCain or Obama to win the election.

EMERSON:

Al Qaeda can subscribe to the Charlie Manson theory of politics. Helter-skelter and let's bring the force of the government against us to create more of an uprising.

BARNDARD:

Which helps to recruit more terrorists. Homeland security officials in Washington say there's no credible threat against the U.S. at this time.

EMERSON:

My belief is that we don't have credible information one way or another that another attack could occur tomorrow without us having any inkling at all about it.

BARNARD:

And all across Maryland tonight, highway signs are urging drivers to report suspicious activity. MDOT says the warnings went up last night not in response to any world event but at the request of something called the Antiterrorism Advisory Council. Terrorist investigator Emerson says Al Qaeda would want Senator Obama in the White House because they might see him as being weak in the face of threats. And Emerson says McCain would be desirable because his expected hard-line approach would stir the pot, if you will, turning out more terrorists.